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Reduced graphene oxide (RGO) supported copper nanoparticles (NPs) were synthesized via a facile in situ procedure using ammonia borane (AB) as a reductant. The as-prepared nanocatalysts exert satisfactory catalytic activity (3.61 mol H 2 mol per catalyst per min), and appear to be the best Cu nanocatalysts up to now for the dehydrogenation of ammonia borane.Ammonia-borane (AB, NH 3 BH 3 ) is nontoxic, stable, environmentally benign, and is considered to be an attractive solid hydrogen storage material due to its high hydrogen mass capacity, high solubility and demonstrated stability in neutral aqueous solutions. 1 With an appropriate catalyst, catalytic hydrolysis of AB can release three mol of H 2 per mol AB at room temperature, which appears to be the most convenient one for portable hydrogen storage applications. 2 So far, not only noble 2-8 and non-noble metal NPs, 9-24 but also their composites have been explored for hydrolytic dehydrogenation of AB. The noble metal-based catalysts exhibit a higher catalytic activity, but they are unsuitable for practical applications due to their limited resources and high price tags. Therefore, the development of efficient and economical non-noble catalysts is of great importance for the practical application of the hydrogen generation/storage systems. Copper (Cu), an abundant element in the earth's crust, has been studied as the catalyst in dehydrogenation reactions. Unfortunately, Cu nanocatalysts are found just to be modesty active for hydrolytic dehydrogenation of AB up to now. 8,10,[14][15][16][17][18]25 For this reason, achieving the high activity of Cu nanocatalysts is of great practical and scientic interest.Graphene, a new class of two-dimensional carbon nanostructure with one-atom thickness, holding many advantages such as outstanding charge carrier mobility, 26 thermal and chemical stability, 27 high specic surface area, 28 and superior electrical conductivity, 29 etc., could be an ideal substrate for growing and anchoring metal NPs with good dispersion. In this work, the RGO supported Cu NPs were prepared within a few minutes by the in situ chemical reduction of mixture containing graphene oxide (GO) nanosheets and Cu(II) ions using AB as a reductant. The as-prepared RGO supported Cu NPs exhibit a high catalytic activity for hydrogen generation from the aqueous of AB at room temperature.In brief, the in situ synthetic and catalytic procedure was achieved by adding AB into the precursor solution containing graphene oxide (GO) nanosheets and CuSO 4 , and the gas generated was measured volumetrically. The Cu 2+ with high reduction potentials (E 0 Cu(II)/Cu(I) ¼ +0.159 eV vs. SHE; E 0 Cu(I)/ Cu ¼ +0.520 eV vs. SHE) was rstly reduced by AB, and then the generated active intermediate Cu-H species with a strong reducing ability can further reduce the GO although they can not be directly reduced by AB. The detailed experimental process could be found in the ESI. †The microstructure of the obtained samples was characterized by transmission electron microscopy (TEM...

Diverse mesoporous CuO nanostructures have been prepared by a facile and scaleable wet-chemical method and reduced to mesoporous Cu nanostructures by using the reductant ammonia borane (AB). These mesoporous Cu nanostructures have been applied as a catalyst for hydrogen generation from the methanolysis of AB. The catalytic results show that the reaction rate and the amount of hydrogen evolution significantly relied on their morphologies. Compared with the nanosheet-like, bundle-like and dandelion-like Cu, the flower-like Cu nanostructures exhibit the highest catalytic activity with a total turnover frequency (TOF) value of 2.41 mol H2 mol catalyst(-1) min(-1) and a low activation energy value of 34.2 ± 1.2 kJ mol(-1) at room temperature. Furthermore, the flower-like Cu nanostructures have also shown excellent activity in recycling tests. The low cost and high performance of Cu nanocatalysts may offer high potential for its practical application in hydrogen generation from the methanolysis of AB.

To measure the safety and efficacy of oxaliplatin (OX) application in neoadjuvant chemoradiotherapy (CRT) for locally advanced rectal cancer (LARC), EMBASE, PubMed, Cochrane Library, and Web of Science were used for a literature search. Cochrane's risk of bias tool of randomized controlled trials (RCTs) was used for quality evaluation. The statistical analyses were performed using RevMan 5.3. In addition, 95% confidence intervals (CIs) and pooled risk ratios (RRs) were calculated. Seven RCTs were included in our meta-analysis. After adding OX to fluoropyrimidine (FU), a marginal significant improvement in disease-free survival was noted compared with FU alone (RR = 0.89, 95% CI: 0.78–1.00; P = 0.05). Neoadjuvant CRT with OX significantly decreased the distant metastasis rate (RR = 0.79, 95% CI: 0.67–0.94, P = 0.007). However, no improvement in the local recurrence rate (RR = 0.86, 95% CI: 0.68–1.08; P = 0.19) was noted. In addition, neoadjuvant CRT with OX also significantly increased the pathologic complete response (RR = 1.24, 95% CI: 1.02–1.51; P = 0.03). Grade 3–4 acute toxicity and grade 3–4 diarrhea was considerably higher for OX/FU compared with FU alone. In conclusion, the use of OX on the basis of FU/capecitabine in preoperative CRT is feasible. LARC patients are likely to benefit from CRT regimens with OX.

The present study reported here synthesis of three novel two-dimensional (2D) polythiophene derivatives with conjugated terthiophene−vinylene side chainpoly{3-(5″-hexyl-2,2′:5′,2″-terthiophenyl-5-vinyl)thiophene-alt-thio-phene} (P1), poly{3-(5,5″-dihexyl-2,2′:5′,2″-terthiophenyl-3′vinyl)thiophene-alt-thiophene} (P2), and poly{3-(4,4″-dihexyl-2,2:5′,2″-terthiophene-3′-vinyl)thiophene-alt-thiophene} (P3)that were synthesized via stille coupling reaction. The terthiophene side chain with different conformations conjugated to the polythiophene main chain via vinyl linkage provided the ability to control the molecular organization, hence affecting the optoelectronic and electrochemical properties of 2D polymers. TD-DFT calculation with the B3LYP/6-31+g(d) function on electronic structures of the monomers was consistent with the experimental results. It suggested that the energetic states of HOMO and LUMO were highly dependent on the side-chain architectures. These polythiophene thin films fabricated by spin-casting show a broader absorption ranges from 300 to 700 nm which was significantly wider than the absorption of pure poly(3-hexylthiophene). When comparing the solid-state absorption spectra of these polymers before and after thermal annealing, P3 displayed the most red-shift in the wavelength range between 450 and 700 nm. It was presumably due to an extended conjugation length resulting from the linear conformation and preferred chain packing, as manifested in the X-ray diffraction. Molecular dynamics (MD) simulation on polymers with different side chains in isolated and packed states suggests planar conformation of the main chain was adopted and regulated by the side chains which were placed in parallel with the mainchain direction. Interestingly, P1 solution revealed an excitation-dependent emission property, suggesting a structural inhomogeneity in solution. Contrary to P1, the PL spectra of P2 and P3 showed only one emission peak at 460 nm, regardless of the excitation energy. Orientation and regiochemistry of the terthiophene side chain had a major impact on the overall optical and electronic properties of the polymer. Moreover, the HOMO and LUMO of these three polymers had been determined through cyclic voltammetry. HOMO of the three polymers were in the following order: P1 > P2 > P3. It implied that the energy level was regiochemistry dependent and directly associated with the linked position between backbone and conjugated side chain. Most importantly, through mesogen-jacketed-like design strategy employed in the present study, the improved packing of these two-dimensional polymers offered insights into structure design to enhance properties that have strong ties to the electronic devices.

Ammonia borane (denoted as AB, NH3BH3) and hydrazine borane (denoted as HB, N2H4BH3), having hydrogen content as high as 19.6 wt% and 15.4 wt%, respectively, have been considered as promising hydrogen storage materials. Particularly, the AB and HB hydrolytic dehydrogenation system can ideally release 7.8 wt% and 12.2 wt% hydrogen of the starting materials, respectively, showing their high potential for chemical hydrogen storage. A variety of nanocatalysts have been prepared for catalytic dehydrogenation from aqueous or methanolic solution of AB and HB. In this review, we survey the research progresses in nanocatalysts for hydrogen generation from the hydrolysis or methanolysis of NH3BH3and N2H4BH3.

In the present study, we examined the factors affecting survival of women with inflammatory breast cancer (IBC) and constructed and validated a nomogram to predict overall survival (OS) in these patients. The cohort was selected from the Surveillance, Epidemiology, and End Results (SEER) program between 1 January 2004 and 31 December 2013. Univariate and multivariate Cox proportional hazards regression models were constructed. A nomogram was developed based on significant prognostic indicators of OS. The discriminatory and predictive capacities of the nomogram were assessed using Harrell's concordance index (C‐index) and calibration plots. A total of 1651 eligible patients were identified, with a median survival time of 31 months (range 0‐131 months), and the 3‐ and 5‐year OS rates were 52.8% and 39.5%, respectively. Multivariate analysis revealed that race (P < .001), marital status (P = .011), N stage (P = .002), M stage (P < .001), hormone receptor (P < .001), human epidermal growth factor receptor‐2 (HER2) (P = .001), surgery (P < .001), chemotherapy (P < .001), and radiotherapy (P = .010) were independent prognostic indicators of IBC. These nine variables were incorporated to construct a nomogram. The C‐indexes of the nomogram were 0.738 (95% confidence interval [CI]: 0.717, 0.759) and 0.741 (95% CI: 0.717, 0.765) for the internal and external validations, respectively. The nomogram had a better discriminatory capacity for predicting OS than did the SEER summary stage (P < .001) or the American Joint Committee on Cancer tumor‐node metastasis staging systems (8th edition; P < .001). The calibration plot revealed satisfactory agreement between the findings and predicted outcomes in both the internal and external validations. The nomogram‐based 3‐ and 5‐year OS predictions for patients with IBC exhibited superior accuracy over the existing models.

In the present study, we have undertaken pharmacodynamic studies of HM-3 in vitro and in vivo. A dual function of HM-3 with various doses was observed. HM-3 at low dose revealed obvious anticancer activity. In contrast, HM-3 at high dose had a tendency to promote tumorigenesis and tumor metastasis. Microarray analysis demonstrated that HM-3 at high dose could up-regulate the transcription of AKT1 and MEK1, which resulted in the promotion of tumorigenesis and metastasis. Therefore, the dose of angiogenesis inhibitors plays a critical role in cancer treatment. In order to achieve the ideal effect of angiogenesis inhibitor drugs on cancer treatment, a ful exploration of administration dose, frequency, and period for this kind of drugs is highly desired.